Can someone please explain in simple terms how these artwork puzzles work? Or where to begin to learn how they are solved? Or how to create such artwork?

I have seen various articles which show pictures/drawings/graphic art, etc. and they were solved, but I didn't see any step-by-step illustrations on "how" they were solved.

Like this Phemex puzzle - https://phemex.com/references/articles/try-to-solve-our-2-btc-puzzle

How do they work and where do you start? Or any examples of solved puzzles showing how they solved them?

Thanks.